I have a set of servers filled each with a bunch of files that can be gzipped. The servers all have different numbers of cores. How can I write a bash script to launch a gzip for each core and make sure the gzips are not zipping the same file?
If you are on Linux, you can use GNU's xargs to launch as many processes as you have cores.
CORES=$(grep -c '^processor' /proc/cpuinfo) find /source -type f -print0 | xargs -0 -n 1 -P $CORES gzip -9
There is an implementation of gzip that is multithreaded, pigz. Since it is compressing one file on multiple threads, it should be able to read from disk more efficiently, compared to compressing multiple files at once.
You might want to consider checking GNU parallel. I also found this video on youtube which seems to do what you are looking for.